论文标题
bane p-n异质结构的运输属性外观bi $ _2 $ _2 $ se $ _3 $/（bi $ _ {1-x} $ sb $ _x $）$ _ 2 $（te $ _ {1-y}
Transport properties of band engineered p-n heterostructures of epitaxial Bi$_2$Se$_3$/(Bi$_{1-x}$Sb$_x$)$_2$(Te$_{1-y}$Se$_y$)$_3$ topological insulators
论文作者
论文摘要
BI基3D拓扑绝缘子材料中寄生大量掺杂的挑战仍然无所不在，尤其是在通过分子束外延（MBE）制备样品时。在这里，我们提出了一种异质结构方法，用于外延BST的增长。薄的N型BI $ _2 $ SE $ _3 $（BS）层用作外延和静电种子，可极大地改善样品特性的晶体和电子质量以及可重复性。在带有P型的BS的异质结构中（Bi $ _ {1-X} $ SB $ _X $）$ _ 2 $（TE $ _ {1-Y} $ SE $ _Y $）$ _ 3 $（BSTS），我们展示了固有的频带弯曲效果，以通过电子构图来调整电子属性，从而使电子属性完全通过厚度进行调整。磁性弱反定位特征的分析表明，随着BST厚度的增加，顶部和底部传导层分离。根据温度和栅极依赖性的传输测量，我们表明薄的BS种子层可以在异质结构内完全耗尽，并通过整个样品厚度通过后门表现出频带的静电调节。
The challenge of parasitic bulk doping in Bi-based 3D topological insulator materials is still omnipresent, especially when preparing samples by molecular beam epitaxy (MBE). Here, we present a heterostructure approach for epitaxial BSTS growth. A thin n-type Bi$_2$Se$_3$ (BS) layer is used as an epitaxial and electrostatic seed which drastically improves the crystalline and electronic quality and reproducibility of the sample properties. In heterostructures of BS with p-type (Bi$_{1-x}$Sb$_x$)$_2$(Te$_{1-y}$Se$_y$)$_3$ (BSTS) we demonstrate intrinsic band bending effects to tune the electronic properties solely by adjusting the thickness of the respective layer. The analysis of weak anti-localization features in the magnetoconductance indicates a separation of top and bottom conduction layers with increasing BSTS thickness. By temperature- and gate-dependent transport measurements, we show that the thin BS seed layer can be completely depleted within the heterostructure and demonstrate electrostatic tuning of the bands via a back-gate throughout the whole sample thickness.
